- From: Bob Ferris <zazi@elbklang.net>
- Date: Mon, 28 Jun 2010 13:58:15 +0200
- CC: Linked Data community <public-lod@w3.org>, Semantic Web <semantic-web@w3.org>
Hi Graham, thanks a lot for this suggestion. I spent some more time in making this concept a bit more solid [1,2]. Here the features that I added/changed in the v0.3 proposal (+ for added, ~for modified): + olo:next - to associate the next slot of a slot in an ordered list ~ olo:length - to enable a single length association to an ordered list ~ olo:length - rdfs:range xsd:positiveInteger (no empty lists!) ~ olo:index - to enable a single index association to a slot in an ordered list ~ anonymous inverse property of olo:slot to rdfs:type owl:FunctionalProperty With that changes it should be possible ... to create a unique neighbourhood relation; the list ends if the slot hasn't a neighbour (that means no is:next property is set) ... to associate a single index to a slot; however, this still not prevents from inserting several slots with the same index ... to associate a single length to an ordered list To model the unique relations for index and length I followed the pattern from here[3]. I think, if the size of the ordered list is defined in its length, which should be used by a rule for validation, why we need than another property, which defines its max length (see also my thoughts about practical application)? I still believe that it isn't possible to guarantee full valid ordered lists, without the use of some rules (only with the rdf:first/rdf:next/rdf:nil pattern). However, rules are created for some purpose, so why not use them (think practical here). Another practical thought is, if something changes in the ordered list, e.g. a new slot would be added, than the graph of the list will be rewritten or a new one would be created (that depends on the used revision mechanism). Comments, suggestions, critics on the new proposal are very welcome. Cheers, Bob [1] http://motools.svn.sourceforge.net/viewvc/motools/orderedlistsonto/branches/orderedlistsonto_v03/rdf/orderedlistontology.n3 [2] http://motools.svn.sourceforge.net/viewvc/motools/orderedlistsonto/branches/orderedlistsonto_v03/gfx/olo_-_orderedlist.gif [3] http://www.w3.org/TR/2004/REC-owl-guide-20040210/#simpleCardinality Am 28.06.2010 10:51, schrieb Graham Klyne: > Bob, > > A desired feature that led to the current rdf:List structure is the > ability to "close" a list - so some separate sub-graph can't "silently" > add properties not in the original. Your pattern might allow this > through additon of a "maxSlotIndex" property on "olo:OrderedList" (not > suggesting this as a design, just an example). > > #g > -- > > > Bob Ferris wrote: >> Hello everybody, >> >> in a longer discussion in the Music Ontology mailing list about how to >> model a playlist, Samer Abdallah came up with a very good proposal[1] >> of modelling a sequence/ordered list (as recently also discussed at >> RDFNext Workshop[2]) as semantic graph (in RDF). >> So, here we go: >> >> - specification[3] (please also note the anonymous inverse properties) >> - concepts and relations in a graphic[4] >> - funky playlist example[5,6] >> >> Again, thanks a lot Samer Abdallah for that cool concept. >> Comments, suggestions, critics are very welcome. >> >> Cheers, >> >> >> Bob >> >> PS: its all OWL based ;) however, we could also downgrade the concept >> on the basis of rdfs:class, if needed. >> >> >> >> [1] >> http://groups.google.com/group/music-ontology-specification-group/msg/305a42362a1e4145 >> >> [2] http://www.w3.org/2009/12/rdf-ws/slides/rdflist.pdf >> [3] >> http://motools.svn.sourceforge.net/viewvc/motools/orderedlistsonto/trunk/rdf/orderedlistontology.n3 >> >> [4] >> http://motools.svn.sourceforge.net/viewvc/motools/orderedlistsonto/trunk/gfx/olo_-_orderedlist.gif >> >> [5] >> http://motools.svn.sourceforge.net/viewvc/motools/orderedlistsonto/trunk/examples/orderedlist_-_example.n3 >> >> [6] >> http://motools.svn.sourceforge.net/viewvc/motools/orderedlistsonto/trunk/gfx/olo_-_orderedlist_example.gif >> >> > > -- --------------------BEGIN-OF-SIGNATURE-------------------- Bob Ferris website: http://elbklang.net e-mail: zazi@elbklang.net --------------------END-OF-SIGNATURE----------------------
Received on Monday, 28 June 2010 11:58:59 UTC